Stoker



March D. J. MOSSHART STOKER Filed May 22, 1925 2 Sheets-Shed 1 P. J. llosshori WITNESSES: IN

VENTOR ATTORNEY March 1 1927' D. J. MOSSHART STOKER Filed May 22 1925 2 Sheets-$heet 2 27 j IO v V. I. ndashort INVVENTOR ATTORNEY Patented Mar. '1, 1927.

UNITED STATES PATENT OFFICE.

DONALD MOSSHART, OF PHILADELPHIA, PENNSYLVANIA, ASSIGNOB TO WEST ING- MANUFACTURING COMPANY, A CORPORATION OF PENNSYL- HOUSE ELECTRIC &

VANIA.

STOKEB.

Application filed May 22, 1925. Serial No. 32,102.

My invention relates to crusher drives, moreparticularly for use in connection with crushers employed to discharge the refuse from automatic stokers and it has for its 5 object to provide means whereby the relative discharge rate of different portions of the crusher may be adjusted in order to accurately meet the operating requirements, in a simple, inexpensive and effective manner.

In the accompanying drawing, Fig. 1 is a side elevation of my improved clinker. roll as applied to an underfeed stoker, shown in section Fig. 2 is a fragmentary view of the structure, partially in section, with parts omitted; and Fig. 3 is an'end view of the apparatus shown in Fig. 2, more clearly illustrating the drive mechanism.

In the operation of I large automatic stokers, particularly of the underfeed type,

3 refuse is frequently discharged from a refuse pit by means of one or more crusher rolls, these rolls generally being driven by a shaft extending the full widthof the stoker so that the rate of ash discharge is substantially 5 uniform across the entire stoker width. It frequently happens that there is an undesirable accumulation of refuse at one portion of the grinder pit and it is desirable to speed up the rtion of the crushing mechanism thereun er in order to remove said excess,

thus accuratel controlling the shape of the fuel bed and t e .efliciency of combustion.

In accordance with the present invention.

I provide a pair of aligned crusher rolls one i of which is hollow and is driven by a. hollow shaft, and the other ofwhich is driven by a shaft projecting through said hollow shaft and said hollow roll. Said concentric shafts are driven by a air of side-by-sid gears which are prefera ly actuated by a pair of pawls, said pawls being oscillated by a common mechanism. Suitable adjustable disengaging means are associated" with the respective pawls whereby the effective are of contact of said members with the respective gears may be adjusted. By this means the angular velocity of one gear and of its associated crusher roll may be adjusted with respect 1 to that of the other gear and roll whereby the desired effect may be secured.

Referring to the drawing for a more detailed understanding of my invention I show at in Fig. 1 the fuel supporting surface of an underfeed stoker of the multi-retort type,

although my invention may equally Well be applied to any other type of grate surface. Fuel is supplied to the grate surface 10 from a hopper 11 by means of a ram operating Within a ram box 12, all as is well known and understood in the art.

The refuse formed by the combustion on the grate surface 10 passes downwardly to a clinker pit 13 from whence it is discharged by a toothed roll shown at 14, all as is wellknown 1n the art and as quite fully described .and claimed in'U- S. Patent No. 1,189,033, issued to Maxwell Alpern on June 27, 1916.

The roll 14 of Fig. 1 is formed in two port1ons 14 and 14" as indicated in Fig. 2, the ortion 14' being hollow and being driven y a hollow shaft 15. The shaft 15 is mounted soas to turn freely on an inner shaft 16 by suitablebearingsurfaces l7 and 18 disposed therebetween. The shaft 16, after traversing a fixed bearing 19, drives the roll 14".

A gear 20 is keyed to the inner shaft 16 and a similar gear 20 is keyed to the outer hollow shaft 15, said gears being of similar s ze and being disposed in side-by-side relation. l

A bridle member 21 is freely mounted on the shafts 15 and 16 so that it is capable of oscillation and is arranged to be oscillated throughout a considerable arc of travel as by a connecting rod 22 operated by any suitable means, such as a motor and worm reduction 23 and a crank member 24.

The bridle member 21carries two dogs 25 t and 26 co-acting respectively with the gears 20 and 20'.

A pair of levers 27 and 28 is disposed between the gears 20 and 20 so as to be capable of oscillation upon the inner shaft 16 and these levers carry pawl guards 2 9 and 30 at their upper ends adapted to underlie the pawls 25 and 26. The lower ends of the members 27 and 28 are connected by suitable links 31 and 32 to control levers 33 and 34- velocity. As the levers 29 and 30 are rotated in a counter-clockwise direction. the guards pass into the arc of travel of the pawls 25 and 26 so that said pawls on the back stroke are lifted from engagement with the respective gears and do not pass into on gagement until a greater or less portion of the forward stroke is completed, whereby the effectiveness of said pawls in driving the associated gears may be reduced substantially to zero.

Having thus described the structure of one form of apparatus embodying my invention, the operation thereof is as follows: In normal operation of the stoker the fuel bed on the grate surface 10 may be of uniform thickness, resulting in a uniform accumulation of refuse in the pit 13, under which conditions the levers 27 and 28 are adjusted to similar positions, resulting in equal angular velocities in the gears and associated crusher rolls. By moving the levers 27 and 28by like amounts, this discharge rate may be adjusted throughout a wide range. Should, however, there be a more rapid accumulation of refuse over one crusher roll than over the other, the proper independent adjustment of the levers 27 and 28 results in the gears 20 and 20' being driven at different angular velocities, with consequent modification of the discharge rate at the respective crusher rolls.

I have shown the drive mechanism as being disposed at one side of the stoker with the crusher rolls projected longitudinally into the pit. If desired, one roll may occupy substantially one-half the stoker width and the other roll may occupy the remaining half of the width, the entire crusher structure being driven from one end, and independent control of the discharge rate at the two sides of the fire thus being secured. On very large stokers, however, it is desirable to duplicate the arrangement described in that two rolls driven from one end of the clinker pit extend only to the middle there of and two similar rolls are driven from mechanism at the other end of the pit, also projecting to the middle thereof. By this means discharge of the refuse is effected by four aligned rolls, each of which may be adjusted in speed independently of the others and thus an extremely flexible control of the shape of the fuel bed may be secured.

While I have shown my invention in but one form, it will be obvious to those skilled in the art that it is not so limited, but is susceptible of various changes and modifications, without departing from the spirit thereof, and I desire, therefore, that only such limitations shall be placed thereupon as are imposed by the prior art or as are specifically set forth in the appended claims.

What I claim is:

1. In a crushing mechanism, the combination with two aligned crushing rolls, one of which is hollow, of av hollow drive shaft connected to drive said hollow roll, a second drive shaft disposed within said hollow shaft and roll and arranged to drive the other ofsaid rolls, and means for operating said shafts at different speeds.

:2. In a crushing mechanism, the combination with a pair of concentric drive shafts, of a hollow crushing roll carried thereby and driven by the outer of said shafts, an additional crushing roll driven by the i11 nor of said shafts, and means for driving said shafts at different angular velocities.

3. In a crushing mechanism, the combination with a pair of concentric drive shafts, of a hollow crushingroll carried thereby and driven by the outer of said shafts, an additional crushing roll driven by the inner of said shafts, a pair of gears of similar size mounted in side-by-side relation and fastened to said shafts respectively, driving pawls associated with said gears, respectively, common oscillating mechanism for said pawls, and independently operable mecha nism for adjusting the effective arcs of travel of said pawls upon the respective gears.

4. The combination with a stoker provided with a refuse receptacle at the rear there of, of crushing discharge mechanism at the bottom of said receptacle embodying a pair of aligned crushing rolls, and means for operating said rolls at differing angular velocities, whereby refuse may be discharged from one portion of said receptacle at a different rate than from another portion thereof.

5. The combination with astoker provided with a refuse receptacle at the rear thereof, of crushing discharge mechanism at the bottom of said receptacle embodying a pair of aligned crushing rolls driven from one end of said receptacle, and meansfor operating said rolls at differing angular velocities, whereby refuse may be discharged from one portion of said receptacle at a different 1 rate than from another portion thereof.

6. The combination with a stoker provided with a refusereceptaclc at the rear thereof, of crushing discharge mechanism at the bottom of said receptacle embodying a pair of aligned crushing rolls one of which is hollow. a pair of coaxial drive shafts for said rolls, one of said shafts being hollow. both of said shafts projecting through said hollow roll and one of said shafts projecting through the other and being connected to the other of said rolls, and mechanism for driving said shafts at differing angular velocities.

7. The combination with a stoker pro- 12 vided with a refuse receptacle at the rear thereof, of crushing discharge mechanism at the bottom of said receptacle embodying a pair of aligned crushing rolls one of which is hollow, a pair of coaxial drive shafts for 13 said rolls, comprising an outer hollow shaft extending through hollow roll and secured thereto and an inner shaft projecting through said hollow shaft and secured to the other of said rolls, a pair of side-by-side gears mounted on saidshafts respectively, common drive mean for said gears, and

means for'varying the efiect of said drive means on each gear, whereby the relative afliigiular velocities of saidgears may be mod- 1 e 8. The combination with a stoker provided with a refuse receptacle at the rear thereof, of crushing dischargemechanism at the bottom of said receptacle embodying a pair of aligned crushing rolls one of which is hollow, a pair of coaxial drive shafts for said rolls, comprising an outer hollow shaft extendingthrou h the hollow roll and setively, a pair of drive pawls, one of w ich I is operatively associated with each of said gears, common means for oscillating said pawls, and means for independently adjusting the arc of engagement of sand pawls with the respective gears, whereby the angular velocities of said crushing rolls may be adjusted. y

In testimony whereof, I have hereunto subscribed my name'this eleventh day of May 1925. I

DONALD J.MOSSHART. 

